Automatic fire alarm



Feb. 12, 1935. E. M. THACKER, JR., ET AL 1,991,004

AUTOMAT IC FIRE ALARM Filed May 17, 1950 2 Sheets-Sheet 1 Feb. 12, 1935. E. M. THACKER, JR, ET AL 1,991,004

AUT OMAT I 0 FIRE ALARM Filed May 1'7, 1950 2 Sheets-Sheet 2 gwuento'cd I {d G Q L Patented Feb. 12, 1935 AUTOMATIC FIRE ALARM 7 Edgar M. Thacker, Jr., and Richard B. Munday, Dayton, Ohio, assignors, by mesne assignments,

to TheFyr-Fyter'Company, Dayton, Ohio, a

corporation of Ohio Application May 17, 1930, Serial No. 453,223

4 Claims. (01. 177-311 This invention relates to fire alarms.

The principal object of the invention is the provision of a compact self-contained portable fire alarm which is adapted to operate effectively in any position, and which'may' be automatically actuated at a predetermined temperature to produce a sustained warning noise I Other objects and advantages of the invention will be apparent from the following description, accompanying drawings and the appended claims. 7

In ,the, drawings which disclose a preferred embodiment of the invention Fig. 1 is a plan view of a fire alarm constructed in accordance with this invention; the housing being shown in section and several of the parts being broken away for clearness of illustration; p r a i Fig. 2 is a sectional view of the alarm taken on the plane of the line 2--2 of Fig. 1; and

Fig. 3 is a side elevational view of the alarm with the housing removed. 1 1

Referring tothe drawings, in which like characters of reference designate like parts throughout the various views thereof, the numeral 10 designates a basetplate of sheet metal or the like to which the mechanism of the fire alarm is attached. A mechanism enclosing cover mem ber 11 is provided, being constructed preferably of a cylindrical side wall section beaded to the top section -to provide an inverted bowl like protective housing-or'cover. This is preferably formed of sheet metal, andis adapted to be attached to the baseplate in a suitable manner such as by means of lugs 12. As shown, these lugs are formed integrally with the cover 11 and are adapted to project through openings 13 in the base 10. Upon assembling the housing cover to the base the lugs 12 are entered-within the holes 13 and are then bent over. to hold the cover to the base plate. The cover member 11 is provided with openings, such as'the spaced slots 14, which are positioned around the peripha cry of the cover member to permit the sound of the alarm to escape. A screen 15 is shown on the inside of the housing adjacent the slots 14 to prevent the entrance of any object which might hinder the operation of the alarm. A slotted opening 16 may be provided in the base plate so that the alarm may be suspended in some convenient location, as from a hook on a wall. It is not necessary'however to suspend the alarm as it will operate effectively in any position; the cover member protecting the operative alarm mechanism and enclosing it i so that the device is fully effective even if partly covered, as when lying in a wastebasket or in some other unusual position.

A bracket 18, which is preferably formed of sheet metal, is attached to the base plate 10 of the alarm as by means' of rivets 19 which extend through the flanges 20 of the bracket 18 and through the base. The bracket'18 with thebase plate 10 forms a supporting struc ture for the alarm mechanism. A potential source of energy, such asa coil spring 22, is provided within the housing to actuate the alarm. The spring is shown positioned within a cup shaped casing 23 and has one of its ends attached thereto by means of a rivet 24. The

spring container 23 is suitably supported for rotational movement upon a winding stem 25 to which the other end of the spring is attached as by means of a rivet 26. The winding stem 25, is supported between the top surface 'of the bracket 18 and the base plate 10, and

is preferably of conventional form similar to the ratcheted winding stem of a clock spring.

It is provided, with a suitable. slot or key engaging means 27 at the lower end which projects "through the base 10 so that the spring may be wound up for use. The winding stem 25 has fixed to it a ratchet 28 which is engaged by a spring pressed pawl 29 suitably supported on the baselO and'adapted to prevent unwinding of the stem 25.

The cup-shaped spring container 23 is pro-, vided with upstanding lugs 30-for the attachment of an alarm actuating drive gear 31 having holes 32 within which the lugs 30 may be .received'ior the attachment of the gear 31 to' the spring housing 23. The gear 31 meshes with a pinion 34 which has fixed toit a gear 35; thepinion 34 and gear 35 comprising an assembly which is positioned for rotational movement upon a stud 38 held between the bracket 18 andthe .baselO. jThe gear '35 meshes with a pinion 34' which has fixed to it a gear 35'; the

which is a duplicate of the pinion and" gear assembly 34-35 and is interchangeable with it.

1 The pinion and gear assembly 34'35 is shown which a gong striking mechanism is positioned.

Economy of production is provided by so locating the various gearshafts that the gears v31,35 and 35 may all be of uniform size and interchangepinion 34'. and gear 35 comprising an assembly at 44, as by welding to the bracket 18. A plate 46, preferably formed of sheet metal, is attached to the pinion 40 for rotational movement therewith and is provided with a pivotally mounted striking member .47 which is free to oscillate within limits upon a pin 48 attached to the rotatable plate .46. If desired, a similar striking member may be positioned at the opposite end.

of the plate, or if a single striking member is used as shown, a balancing weight 50 may be provided so that during rotation the plate 46 will be maintained substantially indynamic balance. A gong 52 is supported by means of a bracket construction comprising arms 53 and 54 which are attached to the arm 43 and bracket 18, so that the striking member 47 may engage apart of the gong as the plate 46 rotates. A bolt 55 provides an attaching means for holding the gong to the supporting structure, preferably so. that the gong is in no way attached directly to the top of the housing cover 11 and bumps or dents on the cover will then not disturb the positioning of the gong or the journals of the rotating shafts. The gong has a slot 56 adjacent the hole 57 through which the gong attaching bolt 55 extends, and the gong supporting structure is provided with aligning means such as the upiturned lug 58 which is adapted to engage the 7 slot 56 so that the gong may always be properly assembled with respect to the striking member. A projecting lug 60 is provided at the rim of the gong for contact with the striking member 47; the slot 56 providing, an eiiective means of anchoring the gong so that the lug 60 will be maintained in proper operating position.

the plate 46 is rotated the lug 60 of the gong is struck by the weighted endfil of the striking member 47 which is thrown outwardly by centrifugal force. Outward movement of the weighted end 61 islimited by suitable means such as a lug 62 which isstruck up from the plate '46. and is adapted to be engaged by a finger 63 on the striking member 47. As the striking ,member is rapidly rotated by the unwinding spring 22 and strikes the gong lug 60, the member 47 tends to rebound so that the vibrations of the gong are not deadened in any way, and if not controlled may rebound an amount sufficient to require considerable travel of the plate 46 to again bring it to striking position. The rebound of the member 47 is limited by a lug 65 which, like the lug 62, may be struck up from the plate 46 ;.the lug 65 being positioned to limit the rebound of the striking member so that it will be caused to strike the lug 60 upon every revolution of the plate 46.

The use of. a striking member such as just described, which rotates continuously in one direction during operation, provides a governing the spring, the impact of the striker will be lessened, and the retarding efiect on the rotatable striker plate-will decrease. For this reason a separate speed governing device need not be employed.

Means are provided for retaining the spring in wound condition and to prevent sounding of the gong until a predetermined temperature is reached. The spring retaining means comprises a temperature responsive element which, when the temperature'reaches a predetermined degree, will release the spring for actuation of the gong." As shown, a lug 67 is attached to the periphery of the spring shell 23 and is adapted tobe engaged by the temperature responsive element 70 which is shown suitably supported upon a bracket '71 held,,as by means of rivets '72, to the base 10 of the alarm structure.

The temperature responsive element comprises a cup shaped member or shell 73 Within which is positioned some suitable fusible or meltable material,

and a screw 74; the head end 75 of which is adapted to be received within the open end of the member'73 while the threaded end 76 of the screw projects through an opening 77 in the bottom or closed end of the member 73. Upon assembling the element 76 a quantity of fusible material 80 is placed within the member '73 between the closed end thereof and the head 75. of the screw; this material being of such character that at normal room temperatures it will remain a solid and hold the cup in'some fixed relatioinship with respect to the screw, and at a predetermined temperature somewhat above normal, say a temperature around 120 F., the material will change from its solid state to perrnit movement of the shell '73 with respect to the screw 74.

As shown, the assembled element '76 is held in operative position by engagement of the projecting end 76 of the screw within a threaded opening 81 of the supporting bracket '71 which is positioned so that thev element 70 will provide an obstruction or stop for the lugfifl to prevent unwinding of the spring. The fusible material 86 in its solid state providesa supportbetween the head '75 of the screw which isheld in the bracket '71 and the shell 73 against which the I 22 is always directed against the element '70 tending to force the shell 73 outwardly to release the spring for actuation of the gong. Should the temperature exceed the degree of heat at which the fusible material softens or melts, the element'lO will; be caused to collapse by such change due to the tension'of spring 22 moving the shell 73 outwardly'on its screw '74 to release the gong actuating mechanism.

The temperature responsive element 70 is positioned within a recess 85 of the cover 11-50 that it is protected against injury which might result from bumps or from contact with other objects. The element is however still in an exposed positionso far as heat is concerned as the wall of the housing 11 does not completely enclose the element but is merely bent inwardly as at 86 and 87 to provide a recess for its protection; Any change in the temperature of the surrounding air will be instantly communicated to the temperature responsive element. Should the temperature of the air in the vicinity of the alarm become heated to a temperature in excess of that at which the material 80 remains in a solid state the element 70 will be promptly c01- lapsed by the springfor sustained actuation of the gong.

In-someinstances of use it is desired that the fire alarm should operate a bell or other sound indicator at a considerable distance from the alarm. Although the firealarm as herein described is portable and ,selfcontained, it is preferably provided with an electric switch des- This bell may be provided in a spot very remote from the fire alarm, being in a distant room or even in a distant building. It should be undere stood that this electric' switch interferes in no manner with the proper operation of the parts of the fire alarm itself, when the switchis not connected.

The switch is preferably mounted on the bracket 18 as shown in Figs. 1 and 3, the threaded stem 94 of the switch being suitably held in place by nuts 95 or the like. The switching arm 96 is preferably adapted to be operated by the lug 6'7, it being understood that when the temperature responsive element permits the lug 67 to move counterclockwise as viewed in Fig. 1, when it reaches the arm 96jit will throw the arm over and close the contact inside of the switch so as to make an'electrical connection between the terminals 91 and 92 so the current can flow through a battery or other suitable source of power, and to the remotely located bell or the like.

While the form of apparatusherein described constitutes a preferred embodiment of the invention, it is to be understood'that the invention isnot limited to this precise form of apparatus, and that changes maybe made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A small self-contained portable fire alarm adapted for normal operation in any position comprising a noise generator, a protective cover housing thereabout, a base supporting said noise generator and said protective cover housing, operating means for said noise generator and releasing means including a material having a low melting point for normally keeping said operating means inefiective and adapted to release said operating means :when a predeterminedtemperature exceeding normal room temperatures has been obtained. 2. A portable self-contained fire alarm adapted fornormal operation in any position comprising a protective housing, a mechanical noise generator in said housing and protected by the housingin all positions of the fire alarm, oper-' ating means for said noise generator including a stop projection, releasing means normally engaging said stop projection for normally keeping said means inefiective and adapted to release said operating means when a predetermined temperature exceeding normal room temperatures has been obtained, and an electric switch in said fire alarm and adapted to be operated by said stop projection upon movement of said operating means.

3. A self-contained portable fire alarm commotor and cover housing, and releasing means for said motor and normally preventing opera: tion of the motor comprising a cup member containinga material having a low melting point, a head member having a head in said cup member, means fixed on said base for holding one of said members in a definite fixed position, and means yieldingly pressed by the spring motor and engaged with the other of said members for normally holding said material under compression between the cup and the headed member until a predetermined temperature is obtained, said'housing having an opening adjacent said cup member for freely exposing the cup member to outside heat effects. V

4. A self-contained portable fire alarm comprising an operating spring motor, a protective cover housing thereabout, sounding means adapted to be operated by said motor, a base 7 supporting said motor and cover housing, and releasing means for said motor and normally preventing operation of the motor comprising a cup member containing a material having a lowmelting point, a head member having a head in said cupmember, means fixed on said base for holding one of said members in a definite fixed position, and means yieldingly pressed by the spring motor and engaged with the other EDGAR M. ,THACKER, JR. RICHARD B. MUNDAY.

- 15 j prising an operating spring motor, a cover housing therefor, sounding means adapted to be operated by said motor, a base supporting said 

